McMurry (kap.5,6)

Question 1

What happens when a molecule has more than one chiral center?

Answer 1

then it is going to have more than two stereoisomers.

Formula for stereoisomers with the chiral centers in mind: 2^n. (although it may have fewer - meso for instance).

Question 2

If a molecule have 2 chiral centers, how many stereoisomers can it have, and what are they then called?

Answer 2

It can have 4, and they can be grouped into 2 groups of enantiomers.

if you take one of the enantiomers and compare it to the other molecule from another enantiomer, they are going to be called diastereomers.

Enantiomers = stereoisomer’s that are mirror images that are nonsuperimposable.

diastereomers = stereoisomers that are not mirror images and not superimposable.

stereoisomers = same molecule but different 3D arrangement of atoms in space.

Question 3

Se tabel 5.2 s.129.

how does the configurations get influenced by enantiomers/diastereomers?

Answer 3

enantiomers have opposite configuration at ALL chirality centers:
2R3S - (enantiomers 2S3R)

diastereomers have opposite configuration at SOME (one or more) chirality centers, but the same configuration at others:
2S3R - (diastereomers 2R2R and 2S2S).
(2R3R == 2R3S og 2S3R )